Abstract: The accumulated negative temperature, the first heating date, the last heating date, heating duration, collective heating area and energy consumption for winter heating in Xi'an during 1986-2002 were comprehensively analyzed. The results show that under the global warming, winter in Xi'an became warmer and heating duration shorter. With the development of economy, the area and energy consumption for collective heating increased continually. In the meantime, the energy consumption per unit area for winter heating decreased year by year, but it did not match the winter temperature well because the energy was not proportionally consumed according to the change of temperature. In order to conserve energy effectively, heating in winter should be timely adjusted according to actual temperature change.

Key words: climate warming, energy consumption, heating, energy conservation